This study aims to assist in the development of an effective vaccine that is appropriate for populations infected with non-B clade viruses, by defining relevant aspects of the immunological responses seen in infections by non-B clade strains of HIV-1, including detailed examination of CTL cross-clade recognition. Relevant issues to be explored include: a) evaluating the spectrum of CTL responses in defined Senegalese cohorts of persons infected with non-B clade viruses, in acute and chronic infection; b) identifying optimal immunogenic epitopes recognized by non-B clade specific CTLs and determining the HLA-restriction of these epitopes, c) determining the degree of conservation or cross-recognition of these CTLs with other clade viruses, namely A, B, C, D and E, and d) determining the ability of HIV-1-specific CTL clones generated from non-B clade infection to inhibit viral replication by other HIV-1 clades. a. Candidate: The candidate received her medical doctorate from the University of California at San Francisco in 1990, and has since completed two and a half years of clinical and post-doctoral fellowship at the Massachusetts General Hospital. b. Sponsor: Dr. Bruce Walker is an Associate Professor of Medicine at Harvard Medical School and Director of the Partners AIDS Research Center (Massachusetts General Hospital). c. Environment: The research and training will be carried out at the Massachusetts General Hospital, with collaborations involving the Harvard School of Public Health, Case Western Reserve University and groups in Uganda and Senegal. d. Training Plan: The candidate will continue research begun during the prior two years as a fellow in Dr. Walker's laboratory.